气候变化领域集成服务门户(CCPortal): Chaos in a simple model of a delta network

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DOI	10.1073/pnas.2010416117
	Chaos in a simple model of a delta network
	Salter G.; Voller V.R.; Paola C.
发表日期	2020
ISSN	0027-8424
起始页码	27179
结束页码	27187
卷号	117 期号:44
英文摘要	The flux partitioning in delta networks controls how deltas build land and generate stratigraphy. Here, we study flux-partitioning dynamics in a delta network using a simple numerical model consisting of two orders of bifurcations. Previous work on single bifurcations has shown periodic behavior arising due to the interplay between channel deepening and downstream deposition. We find that coupling between upstream and downstream bifurcations can lead to chaos; despite its simplicity, our model generates surprisingly complex aperiodic yet bounded dynamics. Our model exhibits sensitive dependence on initial conditions, the hallmark signature of chaos, implying long-term unpredictability of delta networks. However, estimates of the predictability horizon suggest substantial room for improvement in delta-network modeling before fundamental limits on predictability are encountered. We also observe periodic windows, implying that a change in forcing (e.g., due to climate change) could cause a delta to switch from predictable to unpredictable or vice versa. We test our model by using it to generate stratigraphy; converting the temporal Lyapunov exponent to vertical distance using the mean sedimentation rate, we observe qualitatively realistic patterns such as upwards fining and scale-dependent compensation statistics, consistent with ancient and experimental systems. We suggest that chaotic behavior may be common in geomorphic systems and that it implies fundamental bounds on their predictability. We conclude that while delta “weather” (precise configuration) is unpredictable in the long-term, delta “climate” (statistical behavior) is predictable. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Attractor; Bifurcation; Geomorphic models; Prediction
语种	英语
scopus关键词	article; climate change; compensation; controlled study; prediction; sedimentation rate; stratigraphy; weather
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160747
作者单位	Salter, G., Department of Earth and Environmental Sciences, St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN 55414, United States; Voller, V.R., Department of Civil, Environmental, and Geo- Engineering, St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN 55414, United States; Paola, C., Department of Earth and Environmental Sciences, St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN 55414, United States
推荐引用方式 GB/T 7714	Salter G.,Voller V.R.,Paola C.. Chaos in a simple model of a delta network[J],2020,117(44).
APA	Salter G.,Voller V.R.,&Paola C..(2020).Chaos in a simple model of a delta network.Proceedings of the National Academy of Sciences of the United States of America,117(44).
MLA	Salter G.,et al."Chaos in a simple model of a delta network".Proceedings of the National Academy of Sciences of the United States of America 117.44(2020).